Microstructure evolution of SiCp/Al-Ti foils during hot rolling
and reaction annealing
and reaction annealing
(School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China)
Abstract: SiCp/Al-Ti foils were prepared by hot-pressing and hot rolling. The diffusion reaction between Ti and SiCp/Al was investigated and multi-layers of intermetallics formed during reaction annealing at 1 200 °C. The microstructure and the composition in each intermetallic layer were characterized using scanning electron microscope (SEM) equipped with energy dispersive spectroscope (EDS). The products from the reaction between SiC and titanium aluminides were determined by X-ray diffractometer (XRD) and the thermodynamics of the reaction was investigated using differential thermal analysis (DTA). The results show that different reactive layers form in the sample and SiC particles disappear with the formation of intermetallic layers after annealing. Intermetallic multi-layers are determined to be Ti3Al, TiAl and TiAl3. SiC particles react with titanium aluminide during reaction annealing to form Ti3AlC, TiC, Ti5Si3 and Ti3SiC2.
Key words: titanium aluminide; diffusion reaction; SiC; composite